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#pragma once

#include <cmath>

#include "cutlass/cutlass.h"
#include "cutlass/complex.h"
#include "cutlass/tensor_ref.h"

#include "cutlass/util/reference/host/tensor_foreach.h"

namespace cutlass  {
namespace reference {
namespace host {

///////////////////////////////////////////////////////////////////////////////////////////////////

/// Computes the p=2 norm of the elements of a tensor with arbitrary reduction data type.
template <
    typename Element,
    typename Layout,
    typename ElementReduction
>
    ElementReduction TensorNorm(
        TensorView<Element, Layout> view,
        ElementReduction accumulator) {

    TensorForEachLambda(
        view.extent(),
        [&](typename Layout::TensorCoord const & coord) {
        Element element = Element(view.at(coord));
        accumulator = cutlass::norm_accumulate(element, accumulator);
    });
    return std::sqrt(accumulator);
}

/// Computes the p=2 norm of the elements of a tensor.
template <
  typename Element, 
  typename Layout
>
double TensorNorm(TensorView<Element, Layout> view) {

  return TensorNorm<Element, Layout, double>(view, 0);
}

///////////////////////////////////////////////////////////////////////////////////////////////////

} // namespace host
} // namespace reference
} // namespace cutlass

///////////////////////////////////////////////////////////////////////////////////////////////////
